The invention relates to electronic printers and printing systems, and more particularly, to a file upgrading process for such systems.
An important task of the operating system in an electronic printing system is the maintenance of files which are permanent objects recorded on backing storage such as hard disks. A file consists of a sequence of pages, the contents of which must be preserved across system restarts. The file system provides the operating system with facilities for creating, organizing, reading, writing, modifying, copying, moving, deleting, and controlling access to the files. However, a system has to be upgraded when new software is released, a process that replaces files critical to system operation. After the installation is completed, the customer or user expects that the machine will boot and they can start using it. If there is a problem during the upgrade process, then the system needs to be restored back to its original level without destroying all of the customer files. Accordingly, the upgrade process needs to guarantee that the system can be booted afterwards and is usable even though the attempt to upgrade the system with new software was not successful.
While it is known in the prior art to store the operating software for reproduction machine on a hard disk, as shown in U.S. Pat. No. 4,937,864 to Caseiras et al, there is no disclosure to a process for upgrading current system software with a new software release in a printing system.